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Ephemeris: 04/03/2026 – GTAS Astronomy meeting tonight

April 3, 2026 Leave a comment

This is Ephemeris for Good Friday, April 3rd. Today the Sun will be up for 12 hours and 53 minutes, setting at 8:13, and it will rise tomorrow at 7:17. The Moon, 2 days past full, will rise at 10:22 this evening.

The Grand Traverse Astronomical Society will hold its April meeting tonight at 8:00 PM at Northwestern Michigan College’s Joseph H Rogers Observatory. This may be an unstructured meeting, and a good time for anyone interested to ask knowledgeable members anything about the sky or telescopes. Even though our telescope clinic is passed, there will always be someone there to help with your telescope questions or problems. Afterward, about 9 PM if it’s clear, there will be viewing of the heavens through the observatory’s telescopes, featuring Jupiter, its cloud bands and moons. Its Great Red Spot might also be visible. The observatory is located on Birmley Rd. South of Traverse City between Garfield and Keystone roads.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Joseph H. Rogers Observatory of Northwestern Michigan College
Joseph H. Rogers Observatory of Northwestern Michigan College, meeting place of the Grand Traverse Astronomical Society, Traverse City, Michigan.
Categories: Ephemeris Program, GTAS Outreach Event Tags:

Ephemeris:04/02/2026 – Determining the date of Easter

April 2, 2026 Leave a comment

This is Ephemeris for Thursday, April 2nd. Today the Sun will be up for 12 hours and 50 minutes, setting at 8:11, and it will rise tomorrow at 7:19. The Moon, 1 day past full, will rise at 9:14 this evening.

Easter will be celebrated by Western Christian churches this Sunday. Easter is a movable feast in that it falls on a different date each year following the first full moon of spring. It was an attempt to follow the Jewish Passover, which starts on the 15th of the month of Nisan. The Jewish calendar being a lunar calendar, the 15th generally begins at sundown on the night of the full moon. And since the Last Supper was a Seder, according to at least one Gospel, the Christian church wanted to link Easter with Passover as closely as possible using the Roman solar based (Julian) calendar. That’s not always the case, especially with our current Gregorian Calendar. Passover this year began last night at sunset, so this year it is nearly in agreement with the Gospel narrative.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Calendar pages showing the relationship of the first full moon after the vernal equinox and Easter, the following Sunday.
This calendar shows the relationship between Easter, the first full moon of spring, and vernal equinox, the first day of spring. In the calculation of Easter, March 21st is considered the date of the vernal equinox, no matter when it actually falls. This year it fell on the 20th,* even in Europe, and the Holy Land. The full moon date is also what I would call a tabular value. The Moon’s orbit is elliptical so a tabular date may not be the exact date of a full moon. So it may be a day off from the actual full moon date.

*Our Gregorian Calendar will correct for this by making the year 2100, normally a leap year of 366 days, an ordinary year of 365 days. The rule is that century years not divisible by 400 get clipped.

Categories: Concepts, Ephemeris Program Tags:

Ephemeris: 04/01/2026 – No fooling, we’re looking at the bright planets for this week

April 1, 2026 Leave a comment

This is Ephemeris for April Fools’ Day, Wednesday, April 1st. Today the Sun will be up for 12 hours and 47 minutes, setting at 8:10, and it will rise tomorrow at 7:21. The Moon, at full today, will rise at 8:06 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. By 8:40 PM tonight or about a half hour or so after sunset, Venus may be seen very low in the West. Binoculars or a telescope will show a very tiny disc on Venus, because it is pretty much behind the Sun, a good way from us. Over the next 7 months it will be moving closer to us and becoming much larger. Jupiter is the brilliant star-like object more than halfway up in the southwestern sky at 9 PM. At that time Venus will still be visible, setting at 9:57 PM. Mercury, Mars and Saturn are lined up just west of the Sun, but unfortunately are overwhelmed by bright morning twilight.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EST, UT – 5 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Jupiter and Venus with the constellations of the Zodiac at 9 PM.
Jupiter and Venus with the constellations of the Zodiac at 9 PM, or 50 minutes after sunset tonight, April 1, 2026. Created using Stellarium.
The full Moon as seen at 10 PM tonight, April 1, 2026. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Jupiter and Venus as they would be seen in a small telescope with the same magnification.
Telescopic Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. Venus will be visible for a short time near the western horizon, while Jupiter is visible most of the night. Venus’ apparent diameter will be 10.7″, and be 93.6% illuminated. It’s on the far side of the Sun. Jupiter will be 38.8″ in diameter, with its moons shown here for 9 PM, tonight April 1st, 2026. The moons can shift noticably over an hour. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets at sunset and sunrise on a single night.
The naked-eye planets at sunset and sunrise on a single night, starting with sunset on the right on April 1, 2026. The night ends on the left with sunrise on the 2nd. The Moon is missing. It is full today but is south of the ecliptic, while we are viewing from a northerly location. So the full mon rises a bit after sunset and sets a bit before sunrise. Click or tap on the image to enlarge it. Saturn is not visible, being too close to the direction of the Sun. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, April 1st and 2nd, 2026. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.

Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,